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Questions for those that build both classical and steel string guitars. My first Classical commission is about to get going in a couple weeks.

1. When I tap tune a loose plates for a steel string I like to adjust the brace heights and profile till I have a consistent dominant tone bell like, not much woofling but clear. is this the same you look for on a classical? Same question on the back

2. The bridge I will be using is ebony. Is rif cut maple the best choice for the bridge support plate? I would think since there will be no pin holes that quartered or even flat sawn would be fine. What thickness on the bridge plate do you prefer.


3. What plate thicknesses are common on backs tops and sides.

4. Is a solid lining providing anything other than traditional build technique on a classical as opposed to kerfed

(I have Tradition and Technology and other documentation to use as reference but am looking for a wide range of opinions)
MichaelP39015.6784375

bump

Michael,

I suggest that you get the Roy Courtnell book Making Master Guitars if you don't already have it. He covers in detail making classicals by a number of famous makers.

CrowDuck

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Chris Nielsen
Soquel, CA.

Michael, why are you using ebony for the bridge? As far as I'm aware, rosewoods are much more traditionally used. I know Joshua uses BRW, all of the classical builders I know also always use BRW or Mad rose or sometimes padauk, but never ever ebony. I would have thought that the damping characteristics of ebony would be very bad for a nylon stringed guitar (they pretty bad for the higher energy Steel strings). If you must use ebony try Macassar.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Michael,

I'm curious to see the responses for tap tuning the top. The classical tops and braces are so thin already, there's not much room to tap tune. I've asked a similar question before and the consensus is that you can't do much on most of the braces, especially considering they are only 2-3 mm high.

As for the bridge plate, I've always used an off-cut from the top and limit it to about 3mm max, tapering toward the ends and sides.

As far as plate thickness, it really depends on your bracing pattern. In general I'm around 2.5 mm in the middle, and take it down to around 2 mm toward the outside. I may thin the plate a little more around the edge, but I always wait until the box is complete before going any thinner there.

As far as the solid lining, I think it's just tradition, and maybe adds a little cleaner look, but I'm sure you would get just as good of results with kerfed linings. On the top I do use tetallones, and I've heard there are some advantages (mostly with ease of building I think). I know using tetallones allows me to have less mass than traditional linings--and I tend to try and build as light as possible without sacrificing integrity.

Good luck!

John

[QUOTE=MichaelP]
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2. The bridge I will be using is ebony.
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[/QUOTE]

I've been told ebony is too heavy for classical tops. BRW, EIR. Bridge plate I use same as my brace wood. I don't tap tune.Marc39015.8524537037

1. When I tap tune a loose plates for a steel string I like to adjust the brace heights and profile till I have a consistent dominant tone bell like, not much woofling but clear. is this the same you look for on a classical? Same question on the back

Dunno.

2. The bridge I will be using is ebony. Is rif cut maple the best choice for the bridge support plate? I would think since there will be no pin holes that quartered or even flat sawn would be fine. What thickness on the bridge plate do you prefer.

Ebony is way too heavy for a classical bridge. You want to go with a rosewood. And there really isn't a bridge plate as you know it on a steel string. There is a bridge strap or reinforcement in some designs, this sometimes is taken all the way down to a 16th or so in thickness. It would usually be the same material as top or braces. Not a hardwood.


3. What plate thicknesses are common on backs tops and sides.

2mm sides (some people make heavier sides. My backs are 2.4 mm. tops range from 2.4mm around edges to 2.7mm between bridge and soundhole. Real Hauser tops tend to be thicker. Some people go thinner. Flamenco's are like paper.

4. Is a solid lining providing anything other than traditional build technique on a classical as opposed to kerfed

Not that I know of.

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Jim Kirby
kirby@udel.edu

i have never seen an ebony bridge on a classical guitar. has the client specifically requested it?

Michael (and Michael),
On the one classical I built, I used ebony for the bridge. It was at the owner's insistance; I really tried to talk him out of it, but he wouldn't budge.
And, as I feared, the sound was less than desirable.
Perhaps not merely the bridge's fault, but it didn't help. It just *sounds* like there's too much weight on top. Like a runner with ankle weights on.
I would strongly advise against ebony for the bridge. Fretboard, you bet. Bridge, no.

SteveSteve Kinnaird39016.5245949074

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

You might try bois de rose since this rosewood turns dark rather quickly.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Michael,

A classical top is not like a steel string top where you can just shave braces until you get a nice tone and resonation. You need to have a decent sounding tap to the wood before you would even consider using it for a classical top. What material and bracing pattern have you chosen for the top? This will make a difference as to what you are looking for in sound when thinning and bracing it.
Ebony bridge?? enough said already
Bridge plate... if I use one at all it is around 1.5 to 2mm thick and always quarter sawn.

Plate thickness - back is around 2.5mm with four braces and top depends on the species of wood and the bracing pattern. My Spruce tops are usually in the neighborhood of 2.4-2.5mm in the bridge area and can go as low as 2mm around the edges. This all depends on the bracing pattern and the particular piece of spruce.
For cedar around 2.5- 2.6mm in the bridge area and as low as 2.1 or 2.2mm around the edges but once again relative to the piece of wood I am using and the bracing pattern employed.
Kerfed linings will work fine and for fun you might even try reversed kerfing. I have noticed a positive influence when using reversed kerfing.

Happy building!

I used a black ebony bridge on a classical once. Once. It weighed almost 30 grams: good rosewood bridges go less than 24, and can be below 20. You might get away with Macassar, as has been said.

The scantlings you've been given are a good start.

Torres never used a bridge plate. I've found that they add mass and stiffness about in the same proportion, so the tap tones of the assembled guitar are not any higher, it just takes more energy to get them going. I've noted on some classicals with plates or 'Bouchet braces' that the dynamic range seems to be up a notch or two; they don't sound good when played softly, but can be driven harder before they 'break up'.

Thinning the top behind the bridge tends to bring up the bass, and thinning it in the 'wings' between the bridge ends and the edges, the treble. This is also true on steel strings, of course.

I do 'tune' the bracing. It works about the same way as tuning a steel string top, except that you're taking off small shavings instead of whole millimeters of height. I use Chladni patterns, rather than listening for tap tones, and I don't usually listen to the initial sound. They all sound nice when I get them done, though!

I have some black Brazilian if you would like to use it for a bridge!
it has no more mass then the regular Braz. but looks like Ebony -except for the pores !
Mike Collins

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Mike Collins

Thanks Mike.
I am consulting with the client about the bridge. I am trying to convince her to use a rosewood with nice charterer for the bridge and a matching fretboard. but if I can't get her off the Black fretboard and bridge I will get back in touch and get some from you.

Thank you Sir